Effect of electron irradiation on gas sensing properties of Al-Zno Effect of electron irradiation on gas sensing properties of Al-Zno ABOUT THE AUTHORS

Abstract: Al-ZnO thin films are prepared by Silar method and are annealed at 450°C for 1 h. A selected number of samples are irradiated by high-energy electron beam and all are characterized by XRD, SEM and energy-dispersive X-ray spectroscopy. Both irradiated and non-irradiated samples are then placed independently inside a gas chamber kept at rotary vacuum. The gas chamber is maintained at a pressure of 0.20 mb and at a temperature of 350°C. Ethanol vapour is admitted in a controlled manner into the chamber and the resistance of the film is measured continuously before, during and after the admittance of the ethanol vapour. The experiment is repeated for different dosages of irradiation and different doping concentrations of Al and the resistance of the film getting reduced fast and considerably at the admittance of ethanol has been observed. The response and recovery time of the irradiated samples is compared with that of non-irradiated samples of the same doping concentration. It has been noted that both irradiated and non-irradiated samples show a response time of 1 s and recovery time of the irradiated samples is shorter than that of non-irradiated samples

Enhanced LPG Sensitivity for Electron Beam Irradiated Al-ZnO Nanoparticles

Al doped and un-doped ZnO thin films are coated on glass substrate by successive ionic layer adsorption and reaction technique with varying doping concentrations of Al from 3 to 7 at%. The samples are annealed at 450 °C for 1 h in the air. The structural and morphological analysis of the samples are carried out using XRD and SEM. The samples are irradiated with high energy electron beam at a dosage of 5 kGy and its sensing properties are explored. It is observed that the irradiated samples show an enhanced sensitivity to liquefied petroleum gas than that of unirradiated samples at the same doping concentration. The higher response and recovery time of irradiated samples are compared with unirradiated samples. The maximum sensitivity (S = 0.35) with faster recovery time of 25 s is observed for the 7% doped Al-ZnO thin irradiated film.Scopu

Enhanced LPG Sensitivity for Electron Beam Irradiated Al-ZnO Nanoparticles

Al doped and un-doped ZnO thin films are coated on glass substrate by successive ionic layer adsorption and reaction technique with varying doping concentrations of Al from 3 to 7 at%. The samples are annealed at 450 degrees C for 1 h in the air. The structural and morphological analysis of the samples are carried out using XRD and SEM. The samples are irradiated with high energy electron beam at a dosage of 5 kGy and its sensing properties are explored. It is observed that the irradiated samples show an enhanced sensitivity to liquefied petroleum gas than that of unirradiated samples at the same doping concentration. The higher response and recovery time of irradiated samples are compared with unirradiated samples. The maximum sensitivity (S= 0.35) with faster recovery time of 25 s is observed for the 7% doped Al-ZnO thin irradiated film

Graphene oxide nanocomposites based room temperature gas sensors: A review

Over the last few decades, various volatile organic compounds (VOCs) have been widely used in the processing of building materials and this practice adversely affected the environment i.e. both indoor and outdoor air quality. A cost-effective solution for detecting a wide range of VOCs by sensing approaches includes chemiresistive, optical and electrochemical techniques. Room temperature (RT) chemiresistive gas sensors are next-generation technologies desirable for self-powered or battery-powered instruments utilized in monitoring emissions that are associated with indoor/outdoor air pollution and industrial processes. In this review, a state-of-the-art overview of chemiresistive gas sensors is provided based on their attractive analytical characteristics such as high sensitivity, selectivity, reproducibility, rapid assay time and low fabrication cost. The review mainly discusses the recent advancement and advantages of graphene oxide (GO) nanocomposites-based chemiresistive gas sensors and various factors affecting their sensing performance at RT. Besides, the sensing mechanisms of GO nanocomposites-based chemiresistive gas sensors derived using metals, transition metal oxides (TMOs) and polymers were discussed. Finally, the challenges and future perspectives of GO nanocomposites-based RT chemiresistive gas sensors are addressed